maybe_serialize( string|array|object $data )

Serialize data, if needed.

Parameters

$data

(string|array|object) (Required) Data that might be serialized.

Return

(mixed) A scalar data.

More Information

  • Data might need to be serialized to allow it to be successfully stored and retrieved from a database in a form that PHP can understand.
  • Confusingly, strings that contain already serialized values are serialized again, resulting in a nested serialization. Other strings are unmodified.
  • A possible solution to prevent nested serialization is to check if a variable is serialized using is_serialized() 
    if( !is_serialized( $data ) ) {
    $data = maybe_serialize($data);
}

Source

File: wp-includes/functions.php 

function maybe_serialize( $data ) {
	if ( is_array( $data ) || is_object( $data ) ) {
		return serialize( $data );
	}

	/*
	 * Double serialization is required for backward compatibility.
	 * See https://core.trac.wordpress.org/ticket/12930
	 * Also the world will end. See WP 3.6.1.
	 */
	if ( is_serialized( $data, false ) ) {
		return serialize( $data );
	}

	return $data;
}

Uses

Uses Description
wp-includes/functions.php: is_serialized()

Check value to find if it was serialized.

Used By

Used By Description
wp-includes/class-wp-customize-manager.php: WP_Customize_Manager::import_theme_starter_content()

Import theme starter content into the customized state.
wp-includes/option.php: update_network_option()

Updates the value of a network option that was already added.
wp-includes/option.php: add_network_option()

Adds a new network option.
wp-includes/deprecated.php: update_usermeta()

Update metadata of user.
wp-includes/option.php: update_option()

Updates the value of an option that was already added.
wp-includes/option.php: add_option()

Adds a new option.
wp-includes/meta.php: delete_metadata()

Deletes metadata for the specified object.
wp-includes/meta.php: update_metadata_by_mid()

Updates metadata by meta ID.
wp-includes/meta.php: add_metadata()

Adds metadata for the specified object.
wp-includes/meta.php: update_metadata()

Updates metadata for the specified object. If no value already exists for the specified object ID and metadata key, the metadata will be added.

Changelog

Version Description
2.0.5 Introduced.

© 2003–2021 WordPress Foundation
Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/maybe_serialize